Studies on the Seasonal Abundance of Near Threatened Avifauna at Muttukadu Backwaters, Southeast Coast of India

The present study shows the distribution of waterbirds across different seasons with special reference to near-threatened species at Muttukadu backwaters, Tamil Nadu, India observed from July 2021 to February 2024. The Muttukadu backwater (12.8006oN latitude and 80.2363o E longitude) is situated in the southeast coast of India with a surface area of about 871530.999 m2. These backwaters provide a critical habitat for both resident and migratory waterbirds and some of the species use this region as stopover site. A total of 126 bird species were documented in this region. Among them, six near-threatened species such as Black-headed Ibis (Threskiornis melanocephalus), Black-tailed Godwit (Limosa limosa), Curlew Sandpiper (Calidris ferruginea), Eurasian Curlew (Numenius arquata), Oriental Darter (Anhinga melanogaster), and Spotbilled Pelican (Pelecanus philippensis) were observed. For these near-threatened species, relative abundance map for breeding season, non-breeding season, pre breeding migratory season, and post breeding migratory season were calculated during the study period. In addition, Percentage of seasonal modelled population, Percentage of region occupied, Percentage of the modelled range were assessed. The Percentage of seasonal modelled population, percentage of region occupied, percentage of modelled range of Spot-billed Pelican was high among the resident near-threatened population. The percentage of seasonal modelled population was high for Curlew Sandpiper among migratory near threatened species. The percentage of region occupied and the percentage of modelled range for Black-tailed Godwit was high with 11 and 0.7 respectively in the study region. This long-term survey of waterbirds in the study area can be useful for the planning of habitat management strategies.